Method of manufacturing magnetic belts

ABSTRACT

A magnetic belt manufacturing apparatus wherein two continuous webs of magnetic recording material are unwound at equal speeds, and fed into a splicing nip with their longitudinal edges coincident and non-recording sides opposed. Two rolls of pressure sensitive tape are unwound at a speed equal to the web unwind speed, passed through creasing and folding nips, and introduced into the splicing nip between the non-recording sides of the webs with their folded center-lines coincident with the web edges and their exposed adhesive sides extending inwardly from the edges. The flattened tubular web emerging from the splicing nip is cut into a plurality of magnetic recording belts which are conveyed to a packaging station.

United States Patent Buteau et al.

[54] METHOD OF MANUFACTURING MAGNETIC BELTS [72] Inventors: Roland N. Buteau, Westbrook; Ruel E.

Taylor, Jr., West Buxton, both of Maine [73] Assignee: Scott Paper Company, Delaware County,

[22] Filed: Apr. 17,1969 [21] Appl.No.: 817,059

[52] U.S.Cl ..l56/204, 156/227, 156/269 [51] Int. Cl. ..B31f5/00 [58] Field of Search ..156/65, 197, 200, 204, 227,

[ 56] References Cited UNITED STATES PATENTS 2,395,917 3/1946 Sterner ..l56/362 X 2,440,664 4/1948 Irons ..l56/2l8 X 3,086,328 4/1963 Peterson et al. ..156/200 X 3,654,011 45] Apr. 4, 1972 3,136,675 6/1964 Kuts ..156/218 X Primary Examiner-Carl D. Quarforth Assistant Examiner-R. L. Tate Attorney-JohnA. Weygandt, William J. Foley, John W. Kane, Jr. and Martin L. Faigus [5 7] ABSTRACT A magnetic belt manufacturing apparatus wherein two continuous webs of magnetic recording material are unwound at equal speeds, and fed into a splicing nip with their longitudinal edges coincident and non-recording sides opposed. Two rolls of pressure sensitive tape are unwound at a speed equal to the web unwind speed, passed through creasing and folding nips, and introduced into the splicing nip between the non-recording sides of the webs with their folded center-lines coincident with the web edges and their exposed adhesive sides extending inwardly from the edges. The flattened tubular web emerging from the splicing nip is cut into a plurality of magnetic record ing belts which are conveyed to a packaging station.

5 Claims, 8 Drawing Figures Patented April 4, 1972 6 Sheets-Sheet 1 FIG. 1A

FIG. 1C

FlG.1A

FIG .1B

FIG. 2

(See FIG. 1C)

(See F|G.1B)

INVENTORS BUTEAU ROLAND N RUEL E. TAYLOR, JR. BYWJQM, 8144A.

ATTORNEYS Patented April 4, 1972 6 Sheets-Sheet 2 (See FIG. 1A)

RUEL E TAYLOR,JR 0 W M FIG. 1B

ATTORN EYS Patented April 4, 1972 6 Sheets-Sheet 5 INVENTORS ROLAND N. BUTEAU RUEL E. TAYLOR, JR. m-umw sm FIG. 1C

ATTOR NEYS Patented April 4, 1972 6 Sheeis-Sheet' 4.

INVENTORS ROLAND N. BUTEAU RUEL E. TAYLOR,JR.

W mm W W ATTORNEYS Patented April 4, 1972 6 Sheets-Sheet 5 INVENTORS N. BUTEAU RUEL E. TAYLOR, JR.

OON

ROLAND xuqmu 14 M ATTORNEYS Patented April 4, 1972 6 Sheets-Sheet 6 FIG. 6

A v 1 I4 I4 x I4 IIT/ 6|? ns ns 27* -27 am emu ATTORNEYS 1 METHOD OF MANUFACTURING MAGNETIC BELTS BACKGROUND OFTI-IE INVENTION belts to prevent a ragged crease from forming in their brittle magnetic coating during storage, which interleaving adds to the expense of the belts. It is thus desirable to provide dictating b'eltswith two diametrically opposed splices which can be folded flat at these splices to facilitate packaging without rupturing the magnetic recording surface and without using interleaves. Double spliced belts are known, for example, in British Pat; No. 798,246.

It is well known that generally tubular structures can be produced by trimming and butting the longitudinal edges of a single web of flexible material and splicing these edges with a pressure sensitive or thermoplastic tape. (of. Honkanen, U.S. Pat. No. 2,795,263; Pechy, U.S. Pat. No. 2,795,264; Kuts, U.S. Pat. No. 3,136,675; and, Reifenhauser, U.S. Pat. No. 3,] 14,301). The patents to Kuts and to Johnson, U.S. Pat. No. 2,668,324, also disclose that a belt of material can be produced by flattening a generally tubular web and cutting the web transverse to its flow path.

These references, however, do not disclose an apparatus for ma method of producing a continuous, generally fattened tube of flexible material from two webs of flexible material having two flexible tape splices positioned equidistant on the tubes periphery, nor an apparatus for or a method of mechanically folding a flexible pressure adhesive tape.

SUMMARY OF THE INVENTION In accordance with applicants invention, two continuous webs of magnetic recording material are unwound from parent rolls at equal unwind speeds, are passed through aligned slitters which trim and align the longitudinal edges of the webs, and are fed into a splicing nip. The longitudinal edges of the web, as trimmed, are spliced with folded tapes introduced into the splicing nip between the longitudinal edges of the web with the adhesive side of the tapes exposed and the tape folds essentially coincident with the longitudinal edges of the webs.

In the preferred embodiment, each tape is folded by passing it through a tape folding assembly comprising a spider wheel which relaxes the tape to compensate for its elasticity, a creasing nip which creases and partially folds the tape, and a folding nip which folds the creased tape. The spider wheel preferably has a fine speed adjustment to compensate for variations in elasticity. between different rolls of tape. It is also desirable to accurately guide the folded tape into the splicing nip over one or more guide blades extending into the tape fold.

The endless magnetic recording belts produced by cutting the spliced tube transverse to web flow have two internal flexible splices positioned equidistant on the belt periphery which enable it to be folded flat for packaging without creasing the magnetic recording material, thereby eliminating the need for cardboard interleaves. When the belt assumes a rounded configuration in use, the accurate flexible splices butt the adjacent web edges so closely that no indication of a discontinuity in the recording surface is picked up by the recording head.

The belts can be produced at high production speeds in accordance with the invention, thereby significantly reducing the cost of such belts in comparison to the manual methods presently used.

Accordingly, it is a primary object of the invention to provide an apparatus for and a method of producing magnetic belts for dictating machines that can be inexpensively packaged by being folded flat without creating any creases in the magnetic coating thereon.

It is a general object of this invention to provide an apparatus capable of producing a generally flattened tube of flexiblematerial at high operating speeds,

which tube may be cut into belts if desired.

It is a particular object of the invention to provide a tape foldingassembly and method to continuously fold flexible tape at production speeds.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A, 1B and 1C, when assembled as indicated in FIG. 2, comprise a partially diagrammatic side elevation view of an apparatus according to the preferred embodiment of the invention.

FIG. 2 is a diagram illustrating the inter-relationship of FIGS. 1A,1B and 1C.

FIG. 3 is an end elevation, partially broken away, looking from the right side of FIG. 1A and showing the splicing nip and one tape folding assembly.

FIG. 4 is a partially cross-sectional view taken along line4- 4 of F1613.

FIG. 5 is an end elevation of two tape folding assemblies and the splicing nip as viewed from the left of FIG. 1A.

FIG. 6 is a plan viewof the combining rolls which define the splicing nip and the slitters with the webs and folded tapes broken away to show the webs and the nip.

tapes as they are spliced in DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An apparatus according to the preferred embodiment of the invention is shown in side elevation in FIGS. 1A, 1B and IC. The apparatus generally comprises two laterally spaced, parallel frames F and F (shown in FIG. 5) between which the elements hereafter described are mounted. It should be understood that any element of the web unwinding elements that is rotatably driven is rotatably mounted between the frames on a suitable shaft and bearings, one end of the shaft extending through the frame to provide a shaft upon which a driving element, such as a spur gear, a cog pulley or timing belt pulley is mounted.

The discussion will begin with a description of the web unwinding elements. Two rolls of magnetic recording material 10 and 12 rolled with the recording surfaces facing outward are rotatably mounted at the opposite longitudinal ends of the apparatus. In brief compass, two webs I4 and 16 are unwound from the rolls 10 and 12 over guide rolls l7 and conventional tension control arms 18. The tensioned webs 14 and 16 next pass to printers 20 where the manufacturers indicia are printed on the recording side of the webs. A series of guide rolls indicated typically by reference numerals 22 guide the webs through print registers 23 into longitudinally aligned slitter nips formed by slitters 24 and edges 27 (see FIG. 6) of combining rolls 26 and 28 where the edges of the webs are trimmed. The trimmed aligned webs are passed into a splicing nip formed between the opposed combining rolls 26 and 28 where the longitudinal edges of the webs 14 and 16 are spliced in the manner to be later described to form a continuous tube 30. The tube 30 is then passed through a cutting nip formed by an anvil roll 32 and a cutter 34 to form a plurality of magnetic belts 36.

The webs l4 and 16 are driven at equal unwind speeds by frictional contact with the combining rolls 26 and 28 and impression cylinders 38 and 40 of the printers 20, which rolls and cylinders are in turn driven at equal surface speeds by the motor M through the following drive train. The output of the motor M is transmitted to a larger cog pulley 42 of a first double cog pulley 44 by cog belt 46, from a smaller cog pulley 48 of the double pulley 44 to the larger cog pulley 50 of a second double pulley 52 by cog belt 53. The smaller pulley 54 of the double pulley 52 comprises a timing belt pulley 56 and a spur gear 58. A timing belt 60 passes around the timing belt pulley 56 and a timing belt pulley 62 affixed to the impression cylinder 38 to drive the cylinder 38. The spur gear 58 is in meshing engagement with an external spur gear 64 provided on intermediate driving element 66, which element is also provided with a timing belt pulley 68. The impression cylinder 40 is driven by a timing belt 70 passing around the timing belt pulley 68 and a timing belt pulley 72 affixed to the impression cylinder 40.

The spur gear 58 is also in meshing engagement with an idler gear 74 that engages a combining roll gear 76 affixed to the combining roll 26 and an anvil roll gear 78 affixed to the anvil roll 32. The combining roll gear 76 engages a combining roll gear 82 affixed to the combining roll 28, and similarly, the anvil roll gear 78 engages a cutter gear 86 affixed to the cutter 34.-The combining roll 28 and the cutter 34 are eccentrically mounted to vary the spacings of the splicing nip N and the cutting nip. The gears 76, 78, 82 and 86 have involute or similar gear teeth forms which will mesh when their center distances are varied. The diameters of the various driving elements described are selected so that the surface speeds of the impression cylinders 38 and 40 and the combining rolls 26 and 28 are all equal, whereby the webs 14 and 16 are unwound at equal unwind speeds.

A second motor M is provided to drive fountain rolls 88 and 90 of the printers 20 via timing belts 92 and 94, respectively. The fountain rolls 88 and 90 are partially immersed in ink baths 96 and transfer a thin film of ink from the baths 94 to anilox rolls 98 during rotation. The anilox rolls 98 are driven by frictional contact with the fountain rolls 88 and 90, and, in turn, frictionally drive and transfer a film ofink to plate cylinders 100. The plate cylinders 100 have overdrive clutches so that they will rotate at the greater of the rotational speeds imparted by the respective impression cylinders 38 and 40 or by the fountain rolls 88 and 90 so that the frequency of the indicia printed on the webs 14 and 16 can be varied by varying the relative speeds of the motors M, and M The print registers 23 are conventional registers for varying the printing position on the unwound lengths of the webs 14 and 16 so that the indicia printed on the webs are aligned as they enter the splicing nip. The unwound length of the webs after the webs leave the printers 20 is such that the ink dries before entering the splicing nip N.

The slitters 24 are standard double-knived rotary paper slitters bearing against lateral ends 27 (see FIG. 6) ofthe combining rolls 26 and 28 to trim the edges of the webs 14 and 16. The rolls 26 and 28 are of equal width and their ends 27 are aligned so that the web edges, which are trimmed against the ends 27 by the slitters 24, are coincident as they enter the splicing nip. (For the sake of clarity, the slitters 24 are not shown in FIGS. 3, 4 and 5.) Paper shavings are blown away from the slitters by conventional air jets (not shown). The width of the combining rolls can be selected to determine the peripheral length of the belts 36 produced. The width of the belts 36 depends, of course, on the relative speed of the web 30 and cutter 34.

Two tape folding assemblies, indicated generally by reference numerals 102, are shown in FIGS. 1 and as being slidably supported on the frames F, and F by downwardly extending depending flanges 104 which engage grooves 106 provided on the top of tape frames 108 and by a tape frame rod 110 which extends laterally through and between the frames F, and F and pass through guide blocks 112 affixed to the back of the tape frame plates 108.

An assembly 102 is shown in greater detail in FIGS. 3 and 4 wherein a roll 114 of flexible pressure sensitive tape 116, rolled with the adhesive side of the tape 116 facing inwardly toward the center of roll 114,'is rotatably mounted on a spindle 118. The tape 116 is unwound from the roll 114 over a spring-loaded rider wheel 119 by a driven spider wheel 120 having a plurality of radial extensions 121. The radial extensions 121 are slidably mounted in radial slots 122 provided in an extension positioning member 123 and are resiliently secured therein by an endless coiled spring 124 passing through apertures 125 in each extension 121 and a cooperat ing external spring groove 126 in the positioning member 123. The bottom surfaces of the extensions 121 are tapered and bear against a conical hub 127 having the same taper, which hub is threaded onto a cylindrical hub 128 mounted on spider wheel drive shaft 129. The extensions 121 thus will move radially in response to axial movement of the conical hub 127 to vary the outer diameter of the spider wheel 120.

The tape 116 is also driven by a tape drive roll 130 which receives the tape from the spider wheel 120 and guides it through a guiding nip formed by it and a tape guide roll 131 into a creasing nip formed by a creasing wheel 132 and a prefolding wheel 134.

The spider wheel 120, tape drive roll 130, tape guide roll 131, and creasing wheel 132 are mounted on a second frame plate 136 secured to and spaced from the plate 108 so that their axial centers are directly above the splicing nip N to crease the tape 116 at its center. The prefolding wheel 134 is mounted on a bar 135 pivoted between the plates 108 and 136 by a pivot shaft 137 and is forced against the creasing wheel 132 by tensioned spring 139.

As can be best seen in FIG. 4, the prefolding wheel 134 is provided with a V-shaped circumferential groove 138 and the creasing wheel 132 is a relatively flat disc which has the same diameter as the prefolding wheel 134 and which is provided with a relatively sharp circumferential edge 140, which cooperates with the groove 138 to crease the tape 116 at its longitudinal center and to partially fold it.

The circumferential edge 140 of the creasing wheel 132 should be sharp enough to crease the tape without cutting it under spring pressure. In practice, it has been found that a radius in the range of 0.003 to 0.005 inch is satisfactory.

The creased tape 116 is passed over a fixed guide blade 142 to a folding nip formed by two opposed, knurled folding rolls 144 and 146 which are rotatably mounted on frames 148 and 150 and extensions 152 and 154, respectively, with their axes perpendicular to the axes of the wheels 132 and 134. Frames 148 and 150 are affixed perpendicularly to the frame plate 108 and the extensions 152 and 154 are movably secured to the frames 148 and 150 by pivot pins 156. Tensioned springs 158 affixed to the extensions 152 and 154 and the frames 148 and 150 draw the rolls 144 and 146 together, thereby providing pressure for the folding nip. The folding nip insures that the tape remains substantially closed as it enters the splicing nip N.

The creased and folded tape 116 is then passed over an ad justable guide blade 160 which is secured to a lateral adjustable screw 162 passing between the frames 148 and 150. The guide blade 160 is adjustably positioned directly over the center of the splicing nip N with its guiding edge 164 preferably laterally positioned inside the nip N relative to the combining roll edges 27 at a distance substantially equal to the thickness of the creased tape so that the outer surface of the crease is essentially coincident with the trimmed edges of the webs 14 and 16 and the roll edges 27 as the tape joins the webs in the splicing nip N, as shown in FIG. 6. The lateral adjusting screw 162 provides a fine tape positioning means to permit such accurate lateral adjustment of the guiding edge 164 relative to the nip N. The guide blade 160 should, of course, be as close to the splicing nip N as possible. To snugly guide the creased tape 116 over the guiding edge 164, it is preferable to position the creasing nip (i.e., the contact point between the creasing wheel 132 and prefolding wheel 134), inside the guiding edge 164 relative to the combining roll edges 27 and to laterally position the guiding edge 141 of the guide blade 142 intermediate the creasing nip and the guiding edge 164.

With reference now to FIG. 6, two tapes 1 16 are fed into the splicing nip N over the guiding means described above from two tape folding assemblies 102 with their creases 117 aligned with both the trimmed edges of the webs 14 and 16 and with the combining roll ends 27. The exposed adhesive sides of the tape 116, which extend inwardly from the creases 117, are bonded to the webs by the pressure exerted by the combining rolls 26 and 28. The untrimmed webs 14 and 16 are preferably wider than the combining rolls 26 and 28 so that the positioning of the slitters 24 against the combining roll ends 27 insures that the trimmed edges of webs 14 and 16 are aligned with the trimming ends 27 in the nip N. Moreover, by sharply creasing the tapes 116 to form small bending radii and centered foldlines or creases 117 and introducing the creases 117 in alignment with the trimming ends 27 in the nip N, the splice formed between the webs l4 and 16 is such that the webs will abut each other when flattened for use.

Referring once again to FIG. 1, the tape folding assemblies 102 are driven from the Master drive by a cog belt 166 that passes over a combining roll cog pulley 168 affixed to the combining roll 26 and a tape drive pulley 170 affixed to a tape drive shaft 172. With reference now to FIG. 5, wherein the back sides of two assemblies 102 are shown in elevation, the tape drive shaft 172 passes through the frame F, and extends across the backsides of both tape folding assemblies 102 supported in suitable bearings 174, which have hubs keyed to keyways 176 to be rotatable within the races fitted within bearing mounts 180 affixed to the backside of the tape frame plates 108. Two bevel gears 182 are mounted on a shaft 172 by set screws screwed into keyways 176. As best seen in FIG. 4, the bevel gears 182 are meshed with tape drive bevel gears 186 of master tape drive gears 188. The master tape drive gears 188 are combined bevel gears 186 and spur gears 192 and are secured to shafts 190, which shafts extend through the tape frames 108 and 136 and upon which the tape drive rolls 130 are mounted. The spur gears 192 are meshed with spider wheel spur gears 196 mounted on the spider wheel drive shaft 129. The diameters of the various tape driving elements of the assemblies 102 are such that the circumferential speeds of the tape drive rolls 130 equal the circumferential speed of the combining rolls 26 and 28, whereby the webs 14 and 16 and tapes 116 are traveling at equal speed as they enter the splicing nip N.

Since most splicing tapes 116 are elastic and are in a tensioned state when rolled into a roll 114, it is necessary to relax the tape before it enters the splicing nip N to avoid puckering in the tube 30. To this end, the spider wheel 120 is provided in the described embodiment to support a relatively long unwound length of tape 116 on the extensions 121 at a different speed from that of the tape drive roll 130 so that the tape has enough time to relax or contract before it passes through the rest of the apparatus. Tape relaxation renders it dimensionally stable so that it will not subsequently contract. The conical adjustment feature of the spider wheel 120, whereby the radius of the extensions 121 can be varied by changing the axial position of the hub 127 provides a fine speed adjustment relative to the speed of the tape drive roll 130 so that the apparatus can compensate for various tape elasticities and tension elongation.

it should be apparent that other mechanisms could be used for tape relaxation, such as for example spacing two ordinary rolls driven at different speeds far enough apart to give the tape time to relax. The spider wheel 120 described was selected to economize space in performing this function.

With reference once again to FIG. 5, the lateral position of the tape assemblies 102 can be, adjusted by turning handwheels 200 which are secured to threaded shafts 202. The shafts 202 are threaded through the-outer guide blocks 112 secured to the back of the tape frame plates 108 and, when rotated, slide the tape assemblies 102 along the tape frame rod 110 to accurately position the folded tapes 116 over the splicing nip N. The bevel gears 182 and bearings 174 can slide along the keyway 176 to permit this adjustment, whereby the tapes 116 are properly positioned as they enter the nip N.

A suitable material for the tapes 116 is a 1 mil Mylar tape with an acrylic adhesive coating on one side such as Minnesota Mining and Manufacturing Companys Y-9l86. Since the adhesive side of the tape contacts the radial extensions 121, the tape drive rolls 130, the prelrolding wheel 134 and the flattening rolls 144 and 146, it is preferable that these elements be made of an easy release material such as polyethylene or Teflon.

it should be apparent that this invention could be utilized with splicing tapes other than the pressure sensitive tapes described as the preferred embodiment of the invention. If thermoplastic tapes are used, for example, conventional heaters could be provided to heat the combining rolls 26 and 28.

Referring once again to FIGS. 1A and 1C, the continuous tube 30 emerging from the splicing nip N is fed through the cutting nip formed by the opposed anvil roll 32 and cutter 34 where it is cut into a plurality of belts 36.

The belts .36 are passed through a flattening nip formed by a flattening roll 204 and a guide belt 206 onto a conveyor 208 which transports them in overlapping relationship to a tray 210. The belts are counted as they pass a conventional counter-actuated solenoid 212. After a predetermined number of belts have passed the solenoid 212 (e.g., 10m 25), the solenoid actuates a counter arm 214 which moves horizontally and disrupts the overlapping of the belts 36 by-thrusting the selected belts toward the tray, whereby discreet batches of belts are delivered to the tray 210. The belts may then by packaged by merely placing them in appropriate cartons or the like without interleaving.

The conveyor 208 and the belt flattening roll 204 are driven by a gear 215 secured to the anvil roll 32 which in turn drives idler gears 216 and 217 that drive an outer flattening roll gear 218. An inner flattening roll gear 220 engages an outer conveyor gear 222 which drives the conveyor 208 around conveyor rolls 224 and 226 over conveyor guide rolls 228.

The belts 36 have two flexible splices equidistant from each other on their circumference. This enables them to be flattened for packaging without creasing the magnetic recording surface of the webs 14 and 16. Thus, no interruption in the recording surface is produced by folding, and the performance of the belts 36 is enhanced. It has been found in practice that belts can be manufactured. by this apparatus with a splice gap of less than 2.5 mils so that a recording head will give no indication of a discontinuity as it passes over the splice.

By creasing the tape before the splice is made, the fold line is established and there is no tendency for the completed belt to fold in any other location. Since the tape crease 117 is accurately aligned with the trimming edges 27 for the paper strips 14 and 16 where the tape and paper are joined at the nip, the joint is formed within the required dimensional tolerance and there is no tendency for skew or asymmetrical joints. The crease also provides the desired bending radius so as to make the magnetic surfaces form a butt-joint when the finished belt is flattened in use on the mandrel of a dictating machine. In the absence of a sharp crease the radius of the tape fold would result in a wide gap when the joint was opened to flat position in use thereby producing an objectionable magnetic discontinuity.

It'is ourintention to cover all variations and modifications of this invention which do not depart from the spirit and scope of the appended claims.

We claim: i

1. A method of manufacturing a generally flattened tubular structure having two splices positioned essentially equidistant from each other on its periphery, said method comprising: introducing two webs of flexible material into a splicing nip at equal speeds with the longitudinal edges of said webs coincident; mechanically folding two flexible splicing tapes having adhesive on one side thereof; feeding saidl folded splicing tapes into said splicing nip at a speed equal to said web speed between said webs with the fold of one said tape essentially coincident with one said web edge and the fold of the other said splicing tape essentially coin'cidentwith the other web edge, the exposed adhesive-containing sides of said tapes extending inward from said folds; and bonding said tapes and said webs in said splicing nip to form said tube.

2. The method of claim 1 which is further characterized by laterally cutting said tube to form a plurality of belts.

3. The method of claim 1 in which said tape folding step comprises creasing said tape by passing it through a creasing nip and then folding said tape by passing it through a folding mp.

4. The method of claim 1 in which said tapes are relaxed to a dimensionally stable state before said folding step.

5. The method of forming a continuous flattened tube from two continuous equal width webs which are aligned at their edges and joined by continuous flexible splices within the tube extending across each pair of aligned edges comprising the steps of:

feeding a pair of flat webs which are wider than the desired width for said tube to a joining nip which has rolls of width equal to said desired width;

feeding a pair of bonding tapes to a creasing and folding station for forming a longitudinal crease line in said tapes with the tape folded flat on said crease line;

inserting said folded tapes between said webs in said nip with the crease lines aligned with the respective edges of said rolls;

trimming said webs against the edges of said rolls; and

bonding said tapes to the interior surface of said webs in said nip to form said tube. 

1. A method of manufacturing a generally flattened tubular structure having two splices positioned essentially equidistant from each other on its periphery, said method comprising: introducing two webs of flexible material into a splicing nip at equal speeds with the longitudinal edges of said webs coincident; mechanically folding two flexible splicing tapes having adhesive on one side thereof; feeding said folded splicing tapes into said splicing nip at a speed equal to said web speed between said webs with the fold of one said tape essentially coincident with one said web edge and the fold of the other said splicing tape essentially coincident with the other web edge, the exposed adhesive-containing sides of said tapes extending inward from said folds; and bonding said tapes and said webs in said splicing nip to form said tube.
 2. The method of claim 1 which is further characterized by laterally cutting said tube to form a plurality of belts.
 3. The method of claim 1 in which said tape folding step comprises creasing said tape by passing it through a creasing nip and then folding said tape by passing it through a folding nip.
 4. The method of claim 1 in which said tapes are relaxed to a dimensionally stable state before said folding step.
 5. The method of forming a continuous flattened tube from two continuous equal width webs which are aligned at their edges and joined by continuous flexible splices within the tube extending across each pair of aligned edges comprising the steps of: feeding a pair of flat webs which are wider than the desired width for said tube to a joining nip which has rolls of width equal to said desired width; feeding a pair of bonding tapes to a creasing and folding station for forming a longitudinal crease line in said tapes with the tape folded flat on said crease line; inserting said folded tapes between said webs in said nip with the crease lines aligned with the respective edges of said rolls; trimming said webs against the edges of said rolls; and bonding said tapes to the interior surface of said webs in said nip to form said tube. 